The number of victims in the recent Mosul air raids has risen to 511 people, including 187 children under the age of 15, Iraqi officials have said.

The strikes in western Mosul where US-backed troops are fighting the Islamic State group are currently under investigation by Iraqi authorities.

“We don’t know where more bodies will turn up as some have been blasted hundreds of metres from the location of the airstrike,” Laith Sattar of the civil defence force told The New Arab.

“Until now the number of victims has reached 511. Around 200 of the bodies remain unidentified because of the severity of the blast has totally destroyed their facial features,” he said.

Sattar said that the attack was the deadliest bombing raids for civilians since the US invasion of Iraq in 2003.

“A team of international investigators arrived at the site early on Sunday,” he added.

An Iraqi military official told The New Arab that whoever carried out the attack may have used internationally banned weapons.

“Six of these bombs destroyed the targeted street and three adjacent alleys. The charred state of the dead bodies and fused iron and deep craters left by the bombs could not have been from normal weaponry,” the official, who spoke on the condition of anonymity, claimed.

The Iraqi speaker of parliament, Salim al-Jubouri, expressed concern on Saturday about the air raid.

“What’s happening in west Mosul is extremely serious, security agencies must investigate the reason why hundreds of innocent civilians have been killed,” Jubouri tweeted.

It was unclear who carried out the airstrikes, but on Friday the US-led coalition against IS said it was investigating the allegations.

The coalition, which has been bombing the extremists for more than two and a half years, said it had struck a location in west Mosul where civilians were reportedly killed.

“An initial review of strike data… indicates that, at the request of the Iraqi security forces, the coalition struck [IS] fighters and equipment, March 17, in west Mosul at the location corresponding to allegations of civilian casualties,” it said in a statement.